Monitoring equine fitness is important when both training and competing to ensure that training is efficient without prejudicing animal health and welfare whilst aiming for maximal performance. The more information that can be acquired about the horse's metabolic and physiological status during a given workout, the better the assessment of performance, such that data driven decisions can be made to optimize training.
An important aim of training is to stimulate the animal's physiology to adapt to a higher level of exertion, thus improving performance. Different equine sports require different optimizations, for example some events favor endurance (predominantly slow twitch muscles, aerobic exercise) and some favor sprint performance (predominantly fast twitch muscles, and anaerobic exercise) such as thoroughbred racing or show jumping. Training aims to stress aspects of the horse's physiology so that fatigue and the resulting compensation lead to adaptation and improved performance over the medium term.
Research has shown that different levels of exercise intensity stress different aspects of the horse's physiology and metabolism. These levels depend both on the natural ability of the animal and it's current level of fitness. These levels can be determined by the measurement of a number of indicators including analysis of blood chemistry, or more conveniently by measurement of heart rate relative to the individual's maximum heart rate. This measurement is useful in determining a desired level of exercise during training to achieve the continued improvement as the horse's fitness progresses. The ability of the horse to recover after exercise is also a measure of fitness. This can be determined by monitoring changes in heart rate over time relative to the horse's maximum and resting heart rates. Additionally the ability of the muscles to tolerate high levels of lactic acid has been used as an index of performance. Blood lactic acid level has been correlated to heart rates to indicate when exercise is in the aerobic or anaerobic zones.
Over training can lead to injury including dehydration, metabolic distress and damage to bone, ligament, tendon and cartilage, some of which is irreversible. It is therefore important to choose a training regime that stresses the relevant aspect of the animal's physiology, maximizing that stress consistent with the level of fitness of the animal and to do this without causing injury or distress. Providing a complete picture of the horses metabolic and physiologic state with kinetic (speed, acceleration, distance, elevation) data and ambient conditions in combination with feed, farrier, radiological, immunization and therapeutic regimens will result in the most complete data set on which to derive training profiles and assess performance output for individual horses.
Current practice relies on the experience of the trainer and in some cases ‘static’ physiological measurements taken before and after training, and on trackside measurements of speed. These measurements include body temperature, weight, heart rate, respiration rate and in some cases blood chemistry. Performance improvement is most often measured by timing the horse over a standard course.
Recently, equine heart rate monitors (manufactured by Polar, Garmin and others) have been introduced and are used during training or competition allowing a ‘dynamic’ or continuous monitoring of heart rate during exercise. These systems can provide a read out of heart rate and speed when combined with a built in GPS system. Data may be displayed to the rider via a wrist or arm mounted display unit. These devices can be programmed to trigger alerts based on reaching certain heart rates. These systems may log data for download after use to a PC. The trainer then uses software supplied with the monitor to compare performance against previous training sessions to assess changes in performance.
This data can be combined with observations of behavior, feeding, body weight or condition, gait, body temperature and respiratory rate to assess the health of the animal, to regulate feeding, and to establish if training should proceed, or be altered or discontinued.
Kobayashi (Equine Vet J Suppl 1999 Jul. 30:159-62) showed that by standardizing training regimes, heart rate and speed monitoring can provide a quantitative assessment of the effect of training by calculating the theoretical velocity the horse can achieve with a heart rate of 200 bpm (V200). This is achieved by measuring heart rate at a range of speeds and by using linear regression to calculate the theoretical speed at a heart rate of 200 bpm. V200 was shown to increase with fitness. The difficulty with implementation of this method in day to day training is that heart rate and speed measurements must be acquired and V200 calculated manually for each horse, which is a time consuming and skilled task prone to error in a day to day training environment.
WO2004/084624 describes a device in the saddle blanket that monitors equine heart rate and velocity and can transmit this information to a trainer's PC via a radio data link. This allows a trainer to monitor a number of horses during training and automate the calculation of V200. The disadvantage however is that this apparatus requires hard wired connections between the blanket, girth and rider that are inconvenient in operation for example if the rider were to fall, and during mounting and dismounting.
U.S. Pat. No. 4,540,001 describes a heart rate monitor integrated into a girth. This apparatus does not include speed sensing so is limited in its ability to monitor heart rate only.
These inventions do not solve the problem of combining physiological, biochemical, environmental and kinetic information into one device which is obtained during training for on the fly and or retrospective analysis of performance and performance improvement.
What is needed is a device for performance assessment and training, most particularly for use when training a horse. Embodiments of the invention are directed to a device affixed to a horse to monitor the horse during exercise using a combination physiological, biochemical, environmental and kinematic sensors to acquire process and display the performance metrics and type of exercise regime to be performed by the horse based upon a predetermined exercise programme.